For protection of electric lines, such as wires, cables, conductor strips, or connectors, it is known to use fuses, which prevent the electric line from being damaged by excessive current flow.
Typically, a fuse is selected with characteristics which match a weakest element of the electric line to be protected. In this respect, it needs to be considered that heating of the electric line will typically depend on the magnitude of electric current flowing through the electric line and on a time duration for which the electric current is flowing through the electric line. That is to say, damage of the line may be caused by a relatively high electric current flowing for a relatively short time duration or by a lower electric current flowing for a longer duration. This behavior may be represented in terms of a time-current characteristic, e.g., given by the time duration of current flow as a function of the magnitude of the current resulting in a maximum allowable temperature increase of the electric line. For example, in the case of electrical cables a critical aspect is the temperature stability of an insulator of the cable. As a general rule, sensitivity of an electric line depends on various parameters, such as line geometry, conductor material, and insulator material. Further, the sensitivity typically also depends on ambient temperature of the electric line. In view of the above situation, various types of fuses exist so that it becomes possible to select a fuse which suits the characteristics of the electric line to be protected.
Further, it is known to use electronic fuses. An electronic fuse may be implemented on the basis of a semiconductor switch which is opened depending on an electrical current flowing through the protected electric line. By way of example, US 2016/0109212 A1 describes an electronic fuse device which also supports modelling of a fuse characteristic by analog circuitry or by a software model. However, designing analog circuitry to achieve a certain fuse characteristic may be a complex task. Further, implementing a software model of a fuse may result in increased complexity of the electronic fuse device.
Accordingly, there is a need for techniques which allow for efficiently protecting an electric line.